Note: Descriptions are shown in the official language in which they were submitted.
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AQUEOUS ALKALINE LIQUID DETERGENT COMPOSITION
The invention relates to built liquid detergent
compositions. More in particular the invention relates
to aqueous alkaline built liquid detergent
compositions with improved rheologic properties.
Aqueous alkaline built liquid detergent compositions
for use in fabric- or dishwashing machines are well
Xnown. They are often considered to be more convenient
to the user than the equivalent dry powdered or
particulate products, as they are easier to dose,
dissolve more readily, are non-dusting and usually
occupy less storage space. Their formulation, however,
is difficult since, on the one hand, considerable
quantities of builder salts and alkaline agents should
be incorporated to provide consumer-sa~isfactory
detergency and, on the other hand, liquid products
should be stable under a wide range of storage
conditions and should have good pourability for
consumer convenience.
2~
In the prior art the problem of incorporating adequate
quantities of e.g. inorganic builder salts in a liquid
detergent has been approached by providing liquid
suspending media, which are able to support the
undissolved part of the builder salt in the liquid in
a semi-permanent way.
Although by internal or external structuring it has
been possible to formulate liquid media capable of
suspending adequate amounts of such undissolved or
less soluble builders, hitherto it has proved
difficult to formulate compositions of high
alkalinity, which results from the use of alkaline
builder salts or alkaline agents, such as silicates or
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sodium hydroxide, without a very negative effect on
the viscosity behaviour and physical or chemical
stability.
Accordingly it is an object of ~he invention to
provide stable suspending built liquid detergent
compositions of high alkalinity, which have a good
pourability and viscosity behaviour.
It is a further object of the present invention to
provide such compositions in which the surface-active
system is primarily based on nonionic detergents.
In the German Patent Application No. 3.006.333 such
alkaline liquid detergent composition is disclosed
comprising a nonionic detergent and a suspending
system on the basis of a combination of sodium poly-
acrylate and modified polyacrylic acid. Tt ~as
observed that compositions formulated according to the
above disclosure without careful selection of the
nonionic detergent in general showed unacceptably high
viscosity and therefore poor pourability.
It has now been found that a highly alkaline liquid
detergent composition can be formulated which
comprises considerable levels of detergency builders
and alkaline agents, comprising an alkoxylated fatty
alcohol nonionic detergent or mixture of such nonionic
detergents having an over-all ratio between the number
of ethylene-oxide units and propylene- and/or butylene
oxide units of less than 9, and an essentially single
structuring agent of the cross-linked polyacrylate
type.
By way of the invention compositions are obtained
which combine the advantages of high alkalinity,
stability, good viscosity and pourability and easy
formulating.
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Accordingly, the present invention provides an
alkaline built liquid detergent composition which
comprises in an aqueous medium:
S (a) at least 2% by weight of an alkoxylated fatty
alcohol nonionic detergent or mixture thereof
having in the alkylene oxide radical an over-all
ratio between the number of ethylene-oxide units
and the propylene- and/or butylene-oxide units of
less than 9;
(b) from 2 to 30% by weight of an alkaline agent;
(c) from S to 35~ by weight of a detergency buildQr;
and
(d) from 0.1 to 1.0~ by weight of an essentially
single structuring polymeric agent; the
composition having a pH equal to or above 11.
An essential feature of the present invention is the
specific selection of the nonionic detergent, which
is of the fatty alcohol type being condensed with a
mixture of ethylene-oxide and propylene-oxide and/or
butylene-oxide. It is necessary to select the
alkoxylated fatty alcohol or mixture thereof such that
the over-all ratio between the number of ethylene-
oxide units and the propylene~ and/or butylene-oxide
units is below 9, preferably below 2.5 or even 1.8.
The term "over-all ratio" refers to the fact that
either a single alXoxylated alcohol may be used having
in its alkylene-oxide radical a suitable ratio of
ethylene-oxide to propylene- and/or butylene-oxide
units or a mixture of alkoxylated alcohols may be used
having a suitable ratio only on an average.
; The nonionic detergent is normally present in an
amount of at least 2% and in particular of at least 5~
by weight, the amount preferably ranging from 5 to 15%
by weight of the total composition.
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Nonionic detergents for use in compositions of the
present invention can be readily obtained
commercially, such at e.g. those sold under the trade
names Lutensol LF 400 to 1300 ~ex BASF AG~ and
Plurafac RA 30 to 343 (ex Produits Chimiques Ugine-
Kuhlmann)
The nonionic detergent can be used as sole detergent
but other detergent-active ingredients, such as e.g.
the water-soluble anionic sulphate or sulp~.onate
detergents, can be tolerated provided their amount
does not exceed 5% by weight, preferably 3% by weight
or even 1~ by weight of the total composition.
The alkaline agent is in general present in an amount
of from 2% to 30% by weight, preferably 10 to 25~ by
waight of the total composition. Examples of suitable
agents are the alkalimetal hydroxides and sillcates,
such as alkalimetal orthosilicates, metasilicates and
disilicates, sodium meta-silicate being preferred.
Also mixtures of alkaline agents may be used, such as
a combination oE sodium silicate and sodium
hydroxide.
The compositions of the invention contain 5% to 35%,
in particular 10~ to 30% and preferably 10~ to 25~ by
weight of a detergency builder. Typical examples of
suitable detergency builders are the phosphate buil-
ders such as the alkalimetal salts of triphosphoric
acid, pyrophosphoric acid, orthophosphoric acid,
polymetaphosphoric acid and mixtures thereof. Sodium
and potassium triphosphates are preferred. Other
suitable builders include carbonates, zeolites and
organic builders such as citrates and polycarboxylates
such as nitrilotriacetate, and mixtures thereof.
The present compositions are e ternally structured and
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for this purpose they contain an essentially single
structuring or thickening polymeric a~ent. Suitable
agents are found among the alkali-stable polymers.
Especially suitable are the water-soluble polymers of
acrylic acid, cross-linked with about 1% of a poly-
allyl ether of sucrose having an average o~ about 5.8
allyl groups for each sucrose molecule, the polymer
having a molecular weight in excess of 1.000.000.
Examples of such polymers are Carbopol 934, 940 and
941. Carbopol is the Registered Trademark of B.F.
Goodrich Co. Ltd., the manufacturers o~ these
polymers. The preferred polymer is Carbopol 941.
Depending on the viscosity which is desired they may
be included in the range of from 0.1% to 1% by weight,
but preferably their amount varies from 0.2% to 0.8
by weight, and in particular from 0.2 to 0.6% by
weight of the total composition.
The liquid detergent composition of the invention may
~urther contain any of the adjuvants normally used in
fabric-washing detergent compositions, e.g. seques-
tering agents such as ethylenediaminetetraacetate and
diethylenetetraamine methylene phosphoric acid, soil-
suspending and anti-redeposition agents such as
carboxymethylcellulose, polyvinylpyrrolidone and the
maleic anhydride/vinylmethylether copolymer, fluores-
cent agents; hydrotropes; conditioning agents; lather
boosters, perfumes, ~ermicides and colourants.
Further the addition of lather-depressors such as
liquid polysiloxane anti-foam compounds; alkaline
stable enzymes, bleaches, such as e.g. sodium
sulphite, and potassium dichlorocyanurate, may be
necessary or desirable to formulate a complete heavy-
duty detergent composition suitable for use in machinewashing operations. These ingredients can be employed
in the liquid detergent without the risk of undue
~2195~0 C ~Z3 (R)
decomposition during storage, especially if a proper
protective coating is applied.
Compositions of the present invention normally have
viscosities within the range of 0.3 to 3.0 Pa.s (at
20~C and 20 sec~l.), in particular within the range
of 0.5 to 3.0 Pa.s and preferably within the range of
0.6-1.2 Pa.s.
Compositions of the present invention are especially
advantageous having pH-values within the high alkaline
region, in particular values equal to or above 11, but
preferred are pH-values above 12 or even above 13.
The invention will be further illustrated in the
following examples. All percentages used therein are
by weight unless otherwise specified.
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Examples l - 5
-
The following compositions were prepared:
TABLE l
.
1Ingredients lex.llex.21ex.31ex.41ex.51ex-61ex.71
1 1 weight percentages
1Lutensol LF 4~3 1 l0 1 lO 1 lO 1 lO 1 l0 1 2.51 2.51
ISodium ~Cl2) alkylbenzene1 - 1 - 1 O~l1 0.l1 - 1 0-l1 0.l1
1 sulphonate
lPotassium triphosphate 1 1 - 1 - 1 12 1 _ 1 _ 1
1Sodium triphosphate 1 l0 1 l0 1 l0 1 l0 1 - 124-6117-l1
ISodium metasilicate 1 20 1 20 1 20 1 8 1 20 1 - 1 - 1
Carbop~l 941 1 0.41 0.21 0.31 0-51 0-51 0-51 0.51
1Sodium hydroxide 1 - 1 - 1 - 1 8 1 - 1 15 1 15 1
1Optical brightener 1 - 1 - 1 - 1 0.21 0.21 - 1 - 1
1water 1 balance
1pH 1 14
Viscoslty results are presented in Table 2.
TABLE 2
,
1Time a~ter preparatlonl vlscOslty in Pa.s (at 20UC,20 sec~l)
1 1ex.l1 ex-21 ex-31 ex.41 ex.51 ex.61 ex.71
1fresh 1 l.l1 0.91 0.71 l.01 0.91 1.51 1.61
1l wee~ 1 1.21 0.81 0.61 1.21 l.l1 1.51 l.91
1l month 1 l.l1 0.61 0.61 1.21 l.l1 1.51 l.91
12 months 1 1.21 0.71 0.71 1.21 l.l1 1.51 l.91
All example composltions showed excellent stability under a wide
temperature range (-5~, 22UC, 37UC) for at least two months. The
compositions also remained stable during l0 freeze~thaw cycles
~between -5~C and 22UC) of 48 hours each.
